It is common practice to assemble the rotor of a steam turbine by shrinking disks onto a shaft, said disks being provided with cavities facing one another and having female pegs disposed in said cavities in one disk and male pegs disposed in the facing cavities of an adjacent disk with each of the disks being shrunk on while disposing the male pegs of said disks into the female pegs of the already shrunk-on adjacent disk.
The pegs ensure that these disks are properly positioned relative to one another.
The inventor has observed that when the male pegs are in contact with the female pegs there is a risk of stress corrosion, and an object of the present invention is to reduce this risk and eliminate it where possible.